Can some people from non-target schools share their experiences?

I'm a junior at a non-target school and I landed an IB internship at a boutique in Atlanta. I want to end up in NY as a full-time analyst at a BB, but I've been talking to some professionals and they've said that most firms hire all their incoming analysts from their summer analyst pool.

If this is the case, what's my next step? I'm thinking my next steps are either aim for a full-time at my boutique in Atlanta or go shoot for a MSF at a target school.